U.S. patent application number 16/826779 was filed with the patent office on 2020-10-01 for electric power work device.
The applicant listed for this patent is Yamabiko Corporation. Invention is credited to Kenji NAKANO, Hisato OSAWA.
Application Number | 20200306948 16/826779 |
Document ID | / |
Family ID | 1000004749687 |
Filed Date | 2020-10-01 |
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United States Patent
Application |
20200306948 |
Kind Code |
A1 |
OSAWA; Hisato ; et
al. |
October 1, 2020 |
ELECTRIC POWER WORK DEVICE
Abstract
Provided is an electric power work device which includes: a body
case; a work tool protruding forward from a front side with respect
to the body case; a motor; and a battery supplying power to the
motor. The motor is accommodated in the body case and the battery
is detachably attached to a rear side with respect to the body
case. A top handle is extended in a longitudinal direction at an
upside with respect to the body case. The top handle includes, on
an upper surface of a front part thereof, a thumb rest and a power
switch. The power switch is arranged on a side in a lateral
direction of the thumb rest.
Inventors: |
OSAWA; Hisato; (Tokyo,
JP) ; NAKANO; Kenji; (Tokyo, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Yamabiko Corporation |
Tokyo |
|
JP |
|
|
Family ID: |
1000004749687 |
Appl. No.: |
16/826779 |
Filed: |
March 23, 2020 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B27B 17/0008 20130101;
B27B 17/08 20130101; B27B 17/02 20130101; B25F 5/02 20130101 |
International
Class: |
B25F 5/02 20060101
B25F005/02 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 26, 2019 |
JP |
2019-058011 |
Claims
1. An electric power work device comprising: a body case; a work
tool protruding forward from a front side with respect to the body
case; a motor driving the work tool; and a battery supplying power
to the motor, wherein the motor is accommodated in the body case
and the battery is detachably attached to a rear side with respect
to the body case, a top handle is extended in a longitudinal
direction at an upside with respect to the body case, the top
handle includes, on an upper surface of a front part thereof, a
thumb rest and a power switch which drives the motor in an on-state
and stops the motor in an off-state; and the power switch is
arranged on a side in a lateral direction of the thumb rest.
2. The electric power work device as claimed in claim 1, wherein
the top handle includes a gripping part, and the thumb rest is
arranged on a longitudinal axis running through a center in a
lateral direction of the gripping part.
3. The electric power work device as claimed in claim 1, wherein
the power switch is a push-button switch.
4. The electric power work device as claimed in claim 3, wherein
the thumb rest and the power switch are arranged on a recessed
surface formed on an upper surface of the top handle.
5. The electric power work device as claimed in claim 1, wherein
the body case includes, on a left side surface, a side handle
extending in the longitudinal direction, and the power switch is
arranged on a right side of the thumb rest.
6. The electric power work device as claimed in claim 1, wherein
the thumb rest includes an indicator light to indicate an on/off
state of the power switch.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] The present application claims the benefit of priority to
Japanese Patent Application No. 2019-058011 filed on Mar. 26, 2019,
the disclosures of all of which are hereby incorporated by
reference in their entireties.
TECHNICAL FIELD
[0002] The present invention relates to an electric power work
device.
BACKGROUND OF THE INVENTION
[0003] There is a conventional electric chain saw including a body
case having a motor therein, a battery mounted in a rear end part
of the body case, and a top handle formed on an upper part of the
body case (see Japanese Patent No. 5462575 and WO2013/032374A, for
example). Such a chain saw is allowed to have a larger battery than
a case where a battery is accommodated in the body case.
[0004] The chain saw disclosed in Japanese Patent No. 5462575
described above is configured such that a power switch is switched
on/off every time a hand guard attached to a front part of the body
case is tilted. When the power switch is on, the motor is driven,
and when the power switch is off, the motor is stopped.
[0005] Further, the chain saw described in WO2013/032374A includes
a power switch arranged on a front side of a gripping part of the
top handle.
[0006] When an operator works with the conventional chain saw as
disclosed in Japanese Patent No. 5462575, the operator is required
to hold the top handle with the right hand and to hold a side
handle with the left hand. In the conventional chain saw, the
operator is required to take the left hand off the side handle to
manipulate the hand guard so as to switch on/off the power switch
during operation. Therefore, it is difficult for the operator to
manipulate the power switch during operation.
[0007] Further, in the conventional chain saw as described in
WO2013/032374A, there is no space for placing the pad of the thumb
on the front side of the gripping part, so that, when the operator
grips the top handle, the operator is required to put the tip of
the thumb under the top handle. When the top handle is gripped in
this way, the chain saw is less secured to cause a problem of poor
working efficiency.
[0008] The present invention intends to provide an electric power
work device to solve the above-described problems, which allows an
operator to stably grip a top handle and to manipulate a power
switch while the operator holds the body case with both hands so
that the operator can work smoothly.
SUMMARY OF THE INVENTION
[0009] An aspect of the present invention is to provide an electric
power work device including: a body case; a work tool protruding
forward from a front side with respect to the body case; a motor
driving the work tool; and a battery supplying power to the motor.
The motor is accommodated in the body case and the battery is
detachably attached to a rear side with respect to the body case. A
top handle is extended in a longitudinal direction at an upside
with respect to the body case. The top handle includes, on an upper
surface of a front part thereof, a thumb rest and a power switch
which drives the motor in an on-state and stops the motor in an
off-state. The power switch is arranged on a side in a lateral
direction of the thumb rest.
[0010] With the electric power work device of the present
invention, when the operator grips a gripping part, the pad of the
thumb is placed on the thumb rest so that the operator can stably
grip the top handle.
[0011] Further, with the electric power work device of the present
invention, the operator can switch on/off the power switch with the
thumb while gripping the top handle. Therefore, after the operator
turns off the power switch to stop the motor while gripping the top
handle during operation, the operator can turn on the power switch
while gripping the top handle, to promptly resume the
operation.
[0012] As described above, with the electric power work device of
the present invention, the operator can stably grip the top handle
and can switch on/off the power switch while holding the electric
power work device with both hands. Accordingly, the operator can
work smoothly, and working efficiency is improved.
[0013] Further, the thumb rest is arranged near the power switch.
Therefore, even if the operator turns off the power switch by
mistake during operation, the operator can easily turn on the power
switch again while gripping the top handle.
[0014] Still further, in the electric power work device of the
present invention, the power switch is arranged on a side of the
thumb rest so that the length in the longitudinal direction of the
top handle is decreased.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 is a side view of a chain saw according to an
embodiment of the present invention;
[0016] FIG. 2 is a plan view of the chain saw according to the
embodiment of the present invention;
[0017] FIG. 3 is a perspective view of the chain saw, with a
battery removed, according to the embodiment of the present
invention; and
[0018] FIG. 4 is a cross-sectional view of a thumb rest and a power
switch in the chain saw, taken along a line IV-IV in FIG. 2,
according to the embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0019] A description will be given of an example of an embodiment
of the present invention in detail, with reference to the drawings
as appropriate.
[0020] In the present embodiment, a configuration, in which the
present invention is applied to a chain saw to cut a tree, a plate,
or the like, will be described as an example. In the following
description, a cutting part of the chain saw is on the front side
with reference to the longitudinal (front-rear) direction, and a
top handle thereof is on the upper side with reference to the
vertical (up-down) direction.
[0021] As shown in FIG. 1, a chain saw 1 includes a body case 10, a
cutting part 20 set to the body case 10, a motor 30 to drive the
cutting part 20, and a battery 90. In the chain saw 1, the battery
90 attached to the body case 10 supplies power to the motor 30 so
as to drive the cutting part 20.
[0022] As shown in FIG. 3, the body case 10 includes a body part 11
formed of a resin box, and a top handle 40 formed on the upper side
of the body part 11. Thus, the top handle 40 is formed on an upper
part of the body case 10. Further, a side handle 50 is attached to
the left side surface of the body case 10.
[0023] As shown in FIG. 1, the motor 30 is accommodated in a front
part of the body part 11. A battery attachment part 12, in which
the battery 90 is detachably attached, and is formed in the rear
part of the body part 11.
[0024] The motor 30 is a popular electric motor. An output shaft 31
of the motor 30 extends in the lateral direction.
[0025] In addition to the motor 30, a control board (not shown) to
control the driving of the motor 30 and a drive mechanism such as a
driving gear (not shown) coupled to the output shaft 31 of the
motor 30 are accommodated in the front part of the body part
11.
[0026] The battery attachment part 12 is formed on the rear end
surface of the body part 11. The battery attachment part 12
includes a holding part 13 to hold the battery 90 and a battery
case 14 to accommodate a lower part of the battery 90.
[0027] The holding part 13 is formed to have a rear end part of the
body part 11 and a part in a plate shape extending upward from the
rear end part of the body part 11. The holding part 13 is inclined
such that a lower part thereof is located forward with respect to
an upper part thereof. As shown in FIG. 3, the rear surface of the
holding part 13 is an inclined surface which is gradually displaced
forward as extending from the upper end to the lower end.
[0028] The holding part 13 is provided, on the rear surface
thereof, with an attachment/detachment mechanism 15 to attach or
detach the battery 90. The attachment/detachment mechanism 15
includes guide members through which the battery 90 is fitted in
the vertical direction and a support member (not shown) to support
the battery 90 from below.
[0029] When the battery 90 is mounted in the holding part 13, the
battery 90 is slid downward along the attachment/detachment
mechanism 15 to mount the battery 90 in the holding part 13 as
shown in FIG. 1.
[0030] The battery 90 is a popular battery, having a rechargeable
battery such as a lithium ion storage battery accommodated in a
rectangular parallelepiped case extending in the vertical
direction, as shown in FIG. 3.
[0031] As shown in FIG. 1, the battery 90 is formed to have a
height higher than that of the rear part of the body part 11. The
battery 90 of the present embodiment is formed larger than a
battery accommodatable in the body case 10. The battery 90 has a
sufficiently high power and charging capacity suitable for
operation.
[0032] In a state where the battery 90 is mounted in the holding
part 13, the battery 90 is arranged in the body case 10 such that
the longitudinal direction of the battery 90 corresponds to the
height direction of the body case 10. Further, the battery 90
mounted in the holding part 13 is formed larger than the rear part
of the body part 11. The battery 90 is arranged in the vertical
direction to stride across a central part in the height direction
of the rear part of the body part 11. The upper end of the battery
90 protrudes above the rear end of the top handle 40.
[0033] Further, the holding part 13 includes an ejection mechanism
(not shown) to be used for removing the battery 90 from the battery
attachment part 12. While the battery 90 is mounted in the holding
part 13, a lever provided on an upper part of the battery 90 is
manipulated to activate the ejection mechanism, to push up the
battery 90.
[0034] Still further, as shown in FIG. 3, the holding part 13
includes a metal connection terminal 16 on the rear surface
thereof. The connection terminal 16 is electrically connected to
the control board and the motor 30 (see FIG. 1). Once the
connection terminal of the battery 90 is connected to the
connection terminal 16 of the holding part 13, the battery 90
supplies power to the control board and the motor 30.
[0035] As shown in FIG. 1, the battery case 14 is formed at a lower
end part of the battery attachment part 12. The battery case 14 is
a cylindrical part to accommodate the lower part of the battery 90.
The lower part of the battery 90 is inserted into the battery case
14.
[0036] As shown in FIG. 2, the body part 11 is set up, on a right
side part thereof, with the cutting part 20 protruding forward. The
cutting part 20 is a work tool for cutting operation and includes a
guide bar 21 and a saw chain 22.
[0037] The guide bar 21 is a member in a plate shape extending in
the longitudinal direction, and a rear end part of the guide bar 21
is attached to the right side part of the body part 11.
[0038] The saw chain 22 in an annular shape is wound around the
outer periphery of the guide bar 21. A rear end part of the saw
chain 22 is engaged with the drive gear coupled to the output shaft
31 of the motor 30.
[0039] When the motor 30 is driven to rotate the drive gear (not
shown), the saw chain 22 rotates along the outer periphery of the
guide bar 21.
[0040] As shown in FIG. 1, the top handle 40 is formed to continue
to the upper surface of the body part 11 and extends in the
longitudinal direction above the body part 11.
[0041] The top handle 40 includes a front end part 41 protruding
upward from a front end part of the upper surface of the body part
11.
[0042] The top handle 40 includes a rear end part 42 coupled to an
upper end part of the holding part 13 of the battery attachment
part 12. In a state where the battery 90 is mounted in the holding
part 13, the upper end part of the battery 90 protrudes above the
rear end part of the top handle 40.
[0043] The top handle 40 includes a gripping part 43 extending in
the longitudinal direction between the front end part 41 and the
rear end part 42. The gripping part 43 is slightly inclined
obliquely downward as extending from the front end part 41 toward
the rear end part 42.
[0044] The gripping part 43 is a part to be gripped by the operator
when the operator holds the chain saw 1. The operator puts the hand
into a space between the gripping part 43 and the upper surface of
the body part 11.
[0045] The gripping part 43 includes a trigger lever 43a as
operating part to increase or decrease the rotation speed of the
saw chain 22 and a lock release lever 43b to unlock the trigger
lever 43a, in a state where the operator grips the gripping part
43.
[0046] As shown in FIG. 3, the side handle 50 extends in the
longitudinal direction from a front part to a rear part on the left
side surface of the body case 10. The side handle 50 is formed of a
bent columnar member.
[0047] A front end part of the side handle 50 is attached on the
left side surface of the front end part 41 of the top handle 40. A
rear end part of the side handle 50 is positioned rearward and
downward with respect to the output shaft 31 of the motor 30, and
is attached on the left side wall of the battery case 14.
[0048] The side handle 50 is curved between the front end part and
the rear end part thereof to bulge outward with respect to the left
side surface of the body case 10 (see FIG. 2).
[0049] As shown in FIG. 2, the chain saw 1 of the present
embodiment includes a thumb rest 45, a power switch 46, and an
indicator light 47 on the upper surface of the front end part 41 of
the top handle 40.
[0050] The thumb rest 45, the power switch 46, and the indicator
light 47 are arranged on a recessed surface 40a formed on the upper
surface of the top handle 40. The recessed surface 40a is slightly
recessed with respect to the upper end surface of the gripping part
43 (see FIG. 4). Further, the recessed surface 40a includes a
protruding part 40b protruding rightward with respect to the right
side surface of the gripping part 43.
[0051] The thumb rest 45 is an area on which the pad of the thumb
of the right hand is placed when the operator grips the gripping
part 43 with the right hand. The thumb rest 45 is arranged on a
longitudinal axis L running through the center in the lateral
direction of the gripping part 43.
[0052] The power switch 46 is a push-button switch to make the
motor 30 (see FIG. 1) drive in an on-state and make the driving of
the motor 30 stop in in off-state. The power switch 46 is formed to
have a circular shape in plan view, and slightly protrudes with
respect to the recessed surface 40a (see FIG. 4). The power switch
46 is switched on and off every time the power switch 46 is pushed
down.
[0053] When the power switch 46 is pushed in a state where the
driving of the motor 30 is stopped so as to be in an on-state, the
battery 90 supplies power to the control board (not shown), to
change to a state where the driving of the motor 30 is on standby.
Then, when the trigger lever 43a is pulled in a state where the
lock release lever 43b is being pushed down, the battery 90
supplies power to the motor 30 through the control board so that
the motor 30 is driven.
[0054] When the power switch 46 is pushed in a state where the
motor 30 is being driven so as to be in an off-state, the power
supply to the motor 30 is interrupted and the driving of the motor
30 is stopped.
[0055] The power switch 46 is arranged side by side on the right
side of the thumb rest 45. The power switch 46 is arranged on the
protruding part 40b of the recessed surface 40a. Thus, the power
switch 46 is arranged at a position protruding onto the opposite
side (right side) of the side handle 50 (left side) with respect to
the top handle 40.
[0056] The indicator light 47 is a light emitting diode (LED)
arranged in the thumb rest 45. The indicator light 47 indicates the
on/off state of the power switch 46. The indicator light 47 is
turned on when the power switch 46 is in an on-state and is turned
off when the power switch 46 is in an off-state.
[0057] When an object to be cut, such as a tree or a plate, is cut
with the chain saw 1 as shown in FIG. 1, the operator grips the
gripping part 43 of the top handle 40 with the right hand, and
grips the side handle 50 with the left hand to carry the chain saw
1.
[0058] When the operator grips the gripping part 43 of the top
handle 40 with the right hand, the lock release lever 43b is pushed
down with the palm, and the lock of the trigger lever 43a is
released. Further, the operator places the pad of the thumb of the
right hand, with which the gripping part 43 is gripped on the thumb
rest 45 in FIG. 2 so that the operator can stably hold the top
handle 40.
[0059] Next, the operator shifts the thumb of the right hand to the
right to push the power switch 46 so as to be in an on-state.
Accordingly, the indicator light 47 is turned on, and the driving
of the motor 30 is on standby.
[0060] The pad of the thumb of the right hand is then returned to
the thumb rest 45, and when the trigger lever 43a is pulled up with
the index finger of the right hand, as shown in FIG. 1, the motor
30 is driven to rotate the saw chain 22. As a result, the object to
be cut can be cut with the saw chain 22.
[0061] The operator can cut the object to be cut while placing the
thumb on the thumb rest 45 during operation. In this case,
depending on the operation situation, the operator lightly places
the thumb on the thumb rest 45 and grips the gripping part 43 to
perform the cutting operation while stably gripping the gripping
part 43, or pushes the thumb rest 45 with the thumb so as to push
the object to be cut to stably perform the cutting operation.
[0062] When the operation needs to be stopped, the trigger lever
43a is returned to stop the driving of the motor 30, and then the
thumb of the right hand is shifted to the right to push the power
switch 46 so as to be in an off-state. Further, when the operation
needs to be urgently stopped, the power switch 46 is pushed with
the thumb of the right hand so as to be in an off-state, without
the trigger lever 43a returned. Consequently, the driving of the
motor 30 is stopped.
[0063] As shown in FIG. 1, in the chain saw 1 (electric power work
device) as described above, the battery 90 in a large shape is
detachably attached to the rear end part of the body case 10.
Further, the top handle 40 extending in the longitudinal direction
is formed on the upper part of the body case 10. The thumb rest 45,
the power switch 46, and the indicator light 47 are arranged on the
upper surface of the front end part 41 of the top handle 40. The
power switch 46 is arranged on the right side of the thumb rest
45.
[0064] In the chain saw 1 according to the present embodiment, when
the operator grips the gripping part 43, the operator places the
pad of the thumb on the thumb rest 45 to stably grip the top handle
40. Further, the motor 30 is accommodated in the front part of the
body case 10 and the battery 90 in a large shape is attached to the
rear part thereof, to allow the chain saw 1 to be well-balanced in
weight in the longitudinal direction. Therefore, the handling of
the chain saw 1 is improved during operation, to improve working
efficiency.
[0065] In the chain saw 1 of the present embodiment, the thumb rest
45 is arranged on the longitudinal axis L running through the
center in the lateral direction of the gripping part 43. In the
configuration, when the operator grips the gripping part 43 and
places the pad of the thumb on the thumb rest 45, the thumb is
extended along the longitudinal axis L, to allow the operator to
stably grip the top handle 40.
[0066] In the chain saw 1 of the present embodiment, the operator
can switch on/off the power switch 46 with the thumb while gripping
the top handle 40. Therefore, after the operator switches off the
power switch 46 to stop the motor 30 while gripping the top handle
40 during operation, the operator can switch on the power switch 46
while gripping the top handle 40 to resume the operation
promptly.
[0067] In this case, the power switch 46 is arranged near the thumb
rest 45. Therefore, even if the operator switches off the power
switch 46 by mistake during operation, the operator can push the
power switch 46 again while gripping the top handle 40 to continue
the operation.
[0068] As described above, in the chain saw 1 according to the
present embodiment, the operator can stably grip the top handle 40
and can switch on/off the power switch 46 while holding the chain
saw 1 with both hands. Therefore, with the chain saw 1 of the
present embodiment, the operator can work smoothly, to improve
working efficiency.
[0069] In the chain saw 1 of the present embodiment, the power
switch 46 is arranged on the side of the thumb rest 45, to have the
length in the longitudinal direction of the top handle 40
decreased. As a result, the entire chain saw 1 is reduced in
size.
[0070] In the chain saw 1 of the present embodiment, the power
switch 46 is a push-button switch, so that the operator can easily
manipulate the power switch 46 with only the thumb while gripping
the gripping part 43.
[0071] Note that the chain saw 1 of the present embodiment is
configured to include the gripping part 43 so as to be gripped with
the right hand of the operator, and the power switch 46 is arranged
on the right side of the thumb rest 45. It is more difficult to
shift the thumb of the right hand gripping the gripping part 43
toward the right side than toward the left side, to allow for
preventing the power switch 46 from being manipulated by
mistake.
[0072] In the chain saw 1 of the present embodiment, the thumb rest
45 and the power switch 46 are arranged on the recessed surface 40a
formed on the upper surface of the top handle 40. Therefore, the
operator can move the pad of the thumb on the recessed surface 40a
to sense the position of the power switch 46 (see FIG. 4).
[0073] Preferably, the power switch 46 may protrude slightly upward
with respect to the recessed surface 40a. With this configuration,
the operator can easily sense the position of the power switch 46,
and when switching off the power switch 46, the operator cannot
switch off the power switch 46 without moving the thumb upward.
Therefore, the power switch 46 is prevented from being manipulated
by mistake.
[0074] In the chain saw 1 of the present embodiment, the indicator
light 47 is arranged in the thumb rest 45, to indicate the on/off
state of the power switch 46. Therefore, the operator can
accurately grasp the state of the power switch 46, to improve
safety.
[0075] In the chain saw 1 of the present embodiment, the battery 90
is mounted in the battery attachment part 12 such that the
longitudinal direction of the battery 90 corresponds to the height
direction of the body case 10. In the configuration, the center of
gravity of the battery 90 can be positioned more on the front side
even if the battery 90 is increased in size in the height
direction, as compared with a case where the longitudinal direction
of the battery 90 is oriented in the lateral direction. Therefore,
the handling of the chain saw 1 having the battery 90 in a large
shape is improved during operation, and the chain saw 1 is reduced
in size.
[0076] In the chain saw 1 according to the present embodiment, the
upper part of the battery 90 mounted to the battery attachment part
12 protrudes above the rear end part of the top handle 40, and the
battery 90 is inclined so as to be separated rearward from the
gripping part 43. In the configuration, even if the battery 90 is
elongated in the vertical direction, the operator is not disturbed
by the upper part of the battery 90 when gripping the gripping part
43. Therefore, the battery 90 can be made larger without reducing
the operability of the chain saw 1.
[0077] The embodiment of the present invention has been described
above, but the present invention is not limited thereto and can be
appropriately modified within the scope of the present
invention.
[0078] As shown in FIG. 2, in the chain saw 1 of the present
embodiment, the power switch 46 is arranged on the right side of
the thumb rest 45, but may be arranged on the left side of the
thumb rest 45.
[0079] In the chain saw 1 of the present embodiment, the thumb rest
45 and the power switch 46 are arranged on the recessed surface 40a
of the top handle 40, but may be arranged on the upper surface of
the top handle 40, without the recessed surface 40a.
[0080] In the present embodiment, the chain saw 1 applied with the
present invention has been described. However, an electric power
work device applicable with the present invention is not limited to
a chain saw, and the present invention is applicable to various
electric power work devices such as a brush cutter, a hedge
trimmer, and a blower.
* * * * *